Montero, who was already set to earn $5.9 million this year, will get $10 million in 2013 and '14, $12 million in '15 and $14 million in '16 and '17.
"It was a commitment we were willing to make, because we know how important he is to us and to our future," D-backs team president and CEO Derrick Hall said.
With Montero set to be a free agent following this season, the D-backs had approached him this past offseason about a contract extension.
Negotiations did not progress very far, and the two sides called a news conference in March to announce that they were going to table talks until after the season.
As time wore on, though, a couple of things became clear.
First, the D-backs did not have a suitable replacement for Montero in their system. And the more they checked around with other clubs, it was apparent that the catching market was incredibly thin.
On top of that, 10-12 teams were expected to be shopping for catchers this offseason, including big-market teams like the Yankees and Red Sox, so once Montero reached free agency, his price was only going to go higher.
"If he hit the open market, we felt he would have been one of the best out there, and there wasn't really anybody that we thought if we traded for would have been as good as Miguel Montero," D-backs general manager Kevin Towers said. "We all know the closer you get to free agency, the more chance you probably have of losing exclusivity of the player."
Montero was signed by the D-backs as a non-drafted free agent in 2001 for $13,000. He has made his home in the Phoenix area and has grown comfortable with the organization and community as a whole.
As a result, he dreaded the thought of leaving a few weeks ago. So when the D-backs approached Montero's agents about reopening negotiations, he had some very strong feelings about getting a deal done.
"I was pretty clear with my agents that I really wanted to sign here, that I wanted to stay here," Montero said. "I never visualized myself playing for another team to be honest. I felt like this was where I belonged. The most important thing is my family, and my family loves to live here. I like to play happy."
Montero, who has missed the past four games after straining his groin Monday night, has started slowly at the plate this year. In his first 137 at-bats this season, Montero is hitting .255 with two homers and 21 RBIs.
Montero was asked if the contract uncertainty weighed on him at all this year.
"Probably it is, but every time I cross the line, I forget everything and just go out and play and have fun and do my thing," Montero said.
Hitting has never been an issue for Montero in his career, but over the past two seasons, he has made huge strides defensively and in the way he handles the pitching staff.
In addition, Montero is very upbeat and vocal keeping his teammates loose at all times.
"He sets a great example for his teammates," D-backs manager Kirk Gibson said. "Most of all is the energy he brings every day to this ballpark. Unbelievable. It's impressive. He's always digging. Things have been tough this year, but I can assure you every inning that he comes into the dugout, he voices and articulates to his teammates never to give in. He's been an All-Star. We want him to be a world champion."
Montero vowed that his approach would not change now that he is making big money and that he would not put added pressure on himself to live up to the deal.
The Venezuelan native was then asked if when he started his pro career that he ever thought he would be making this kind of money.
"When I first signed, I signed for $13,000, it's unbelievable the difference," Montero said. "I just wanted to play in the big leagues and be a big league player. I never thought about making as much money as I'm going to make right now. I just wanted to play for a long time and be a good teammate and a good clubhouse guy. That way, if I don't make the big leagues, maybe I could be a coach or something like that."